SAN FRANCISCO (KCBS) — Environmentalists on Wednesday pushed for curbs on plastic water bottle sales in San Francisco City as well the Golden Gate National Recreation Area.

San Francisco City Supervisor David Chiu is making a proposal on Wednesday to ban plastic water bottles at big events if water stations are available. He would also prohibit the sale of plastic bottles in all future city contracts, except sporting events and the airport.

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“Every 27 hours we produce enough plastic water bottles to ring around the globe, and they are amazingly bad for the environment,” Chiu said.

“We are literally discarding billions of plastic water bottles. Most of these end up in land use and the ocean. Only five percent are recycled in the U.S. and it takes over 1,000 years for every plastic water bottle to biodegrade.”

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Meanwhile, environmental activists are gathering at the Presidio on Wednesday calling for a ban for plastic bottle water sales at GGNRA parks as well as Yosemite National Park.

There is already a ban in effect at Muir Woods and National Parks spokesman Howard Levitt thinks that will gradually extend to the entire GGNRA.

“We are heading in that direction. That is our commitment, and we’ll be getting to it just as soon as we can,” he said. “We can imagine a time when plastic water bottles would not be for sale in the park.”

But he said also said that National Park Service can’t extend a ban without an extensive review and without providing water stations where people can refill their bottles for free.

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